Will exhaust effect performance of vehicle?

Yes, well… it almost does. This is why race cars tend to be louder.
There is not much after the manifold

Some nice tubing and that is about it. (they still have specific measurements). Exhaust systems certainly play a critical role in the performance of every engine.


Dual exhaust systems have long been recognized as a performance perk and interconnecting H-pipes and X-pipes have become the norm for high-performance exhaust systems.
But this will only apply to 4 stroke engines. On a two-stroke engine, there is an expansion chamber or tuned pipe, tuned exhaust.

Two strokes can function with significantly better power if they are aided in these 4 ways:

1) pulling in extra intake charge up from the crankcase into the cylinder,

2) pulling in extra intake charge from the carburetor into the crankcase,

3) preventing the intake charge from escaping through the exhaust port (so it can be used for combustion),

4) boosting the compression at top RPM for a faster burn and more power.

 

How an expansion chamber works:
For those who want to get into exhaust design, there is a header-pipe-design program available on the internet called Pipe Max. It’s offered by Meaux Racing Heads and you can download it from their website at MaxRaceSoftware. It incorporates enough user data to function as an engine simulation program and it does calculate torque and horsepower output based on VE and header specs. It provides a lot of info about dimensions and the proper design to accommodate wave tuning. You input all the engine information along with details about cylinder heads and camshaft and it calculates the optimum primary pipe diameters and cross-sectional areas, primary tube lengths and collector specifications for optimum performance.

The exhaust system of the “common car”, has a few more parts and components.
But the main use for those or the aim is to avoid noise and pollution. Not to increase performance. Of course, it is still designed for max possible performance, but they use the extra components because, by law, they have to keep the vehicle under a certain “db noise”, and as “clean” as possible.